The sudden death Wednesday of actor James Gandolfini at 51 seems shocking not just because he was so young but because the iconic character he created, Tony Soprano, was so filled with life.

Soprano, a New Jersey mob boss, was unlike other Hollywood gangsters: a ruthless killer secretly seeing a psychiatrist because he was prone to panic attacks and blackouts. It rewrote the books on conflicted characters and brought Gandolfini instant fame — and three Emmy awards.

He was a natural for the role, being Jersey born and bred, though he was nothing like Tony Soprano in real life. Gandolfini did not embrace his newfound celebrity; instead, he shrank from giving interviews and chose smaller character roles for his later film and stage work. But there was one area in which he did use his star status, and that was in his philanthropic work, particularly in his devotion to wounded veterans.

The actor produced two documentaries for HBO, one in which vets of the Iraq War spoke of their combat experiences and another that traced the history of combat-related stress in US wars. He also visited troops in Afghanistan and Iraq “just to walk around and say hello to the guys,” something he was prompted to do by his father’s World War II experiences.

In the wake of the 9/11 attacks, he visited New York City firehouses and met with first responders. After moving to Los Angeles, he began raising funds for the local police foundation.

Gandolfini certainly was no conservative; he even spoke at a rally protesting the 2004 GOP convention here. But he felt an obligation to use his celebrity for the kind of causes that most of Hollywood traditionally scorns. That, and the indelible power of his most memorable role, are why so many are mourning his passing.